package com.itheima.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.common.BaseContext;
import com.itheima.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否登录
 */
//@WebFilter(filterName = "LoginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器,支持通配符
    public static final AntPathMatcher PATH_MATCHER=new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        //强转
        HttpServletRequest request= (HttpServletRequest) servletRequest;
        HttpServletResponse response= (HttpServletResponse) servletResponse;

        //1. 获取本次请求的URI
        String requestURI = request.getRequestURI();
        //定义不需要处理的请求路径
        String urls[]={"/employee/login","/employee/logout","/backend/**","/front/**","/common/**"};
        //2. 判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
        //3. 如果不要处理,直接放行
        if (check){
            filterChain.doFilter(request,response);
            return;
        }
        //4. 接受浏览器中的session数据,因为登录成功后会把信息发送到浏览器
        if (request.getSession().getAttribute("employee")!=null){
            Long id= (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(id);
            filterChain.doFilter(request,response);
            return;
        }
        //5. 如果未登录返回登录结果,通过输出流方式向客户端页面响应数据
        log.info("被拦截了");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
    }

    public boolean check(String urls[],String requestURL){
        for (String url : urls) {
            boolean match=PATH_MATCHER.match(url,requestURL);
            if (match){
                return true;
            }
        }
        return false;
    }
}
